Trying to solve this problem, I decided to (again) re-install Adobe Acrobat Reader DC.
As usual I removed it via “Add or remove programs”.
All went fine.
But then I cannot install the new one due to “Old/New Acrobat version already installed”:
So, I rebooted the machine. The same message.
Why it says that the “Old/New Acrobat version already installed” if it was removed?
If you click “Finish” there is:
But it is not installed.
How to fix?